A totally implantable artificial lung (IAL) is presented. The IAL is designed to fully support adult human patients who require long term (1- month) artificial has exchange support necessary for treatment and recovery. the IAL will provide a bridge to lung transplantation when lung recovery is impossible. The IAL is designed to be perfused entirely by the right ventricle while the device is placed in parallel with the native lung (i.e., pulmonary artery to left atrium). An important advantage of the IAL over intravascular oxygenators is that the advantage IAL reduces impedance seen by the right ventricle. In Phase I, MC3 prototyped several extremely low resistance, highly efficient artificial lungs, and in collaboration with the University of Michigan, successfully implanted ten devices in 24 -hour sheep experiments. In Phase II, and IAL design will be modified to match resistance and compliance of the pulmonary circulation. The geometry of the device will be modified to prevent thrombosis. Custom-extrusion solid silicone fibers will be used to prevent plasma leakage. Extensive bench testing is planned, including flow visualization and hemolysis analysis. The IAL will be tested in a sheep model, with he goal of achieving 1- month total gas exchange support. PROPOSED COMMERCIAL APPLICATIONS: The commercial potential for this device is extensive. The number of potential bridge to lung transplant candidates in the US is currently over 1,000 of which 50% ar rejected because of scarcity of available donor lungs, infectious complications, and simply because they cannot tolerate the surgical procedure, thereby making them too high a risk for very precious organs.